The demand for ice cream and similar products is extremely seasonal and may even vary considerably from day to day during the peak season. In order to meet demand and be able to supply the products to keep pace with varying demand, a sufficient surplus of the products is, therefore, often produced during the off-season so as to cover the general increase in demand (and also expected temporary demand peaks) during the coming peak season. This often implies that large product stockpiles must be built up and stored for periods of time whose length cannot be foreseen.
Since products of the type mentioned here are extremely sensitive to storage and bacterial attack, it is important that the production and storage of such products be effected in such a manner and under such conditions that the risk of total quality loss or quality deterioration during the period of time from production and packaging of the products and up to their consumption is wholly eliminated or at any rate reduced to a minimum, such that it be possible for the products, after storage, to be consumed with substantially retained pristine freshness qualities and in a condition fully acceptable from the point of view of health.
In order to retain the freshness qualities of the produced product such as flavour, colour, consistency etc., it has hitherto often been necessary to store the packed product in cold storage adapted for this purpose and set at extremely low storage temperatures of as low as approx. -30.degree. C.
Since cold storage is extremely energy- and cost-consuming, it has always been desired in this art to find alternative production and storage methods which, in terms of both energy and costs, consume less than the previously employed cold storage and which, at the same time, make possible a correct storage of the product from the points of view of consumer health and quality retention.